Differing default mode network activities in men with homosexual or heterosexual preferences

Area of Science:

• Neuroimaging
• Neuroscience
• Brain Activity

Background:

• Previous neuroimaging studies indicate structural and functional brain differences between homosexual and heterosexual men.
• The precise neural underpinnings of homosexual orientation remain largely unexplored.

Purpose of the Study:

• To investigate the relationship between homosexual preference and brain activity measures.
• Characterize differences in fractional amplitude of low-frequency fluctuation (fALFF) and functional connectivity (FC) in resting-state brain activity.

Main Methods:

• Acquired echo planar magnetic resonance imaging data from 26 homosexual and 26 age-matched heterosexual men during a resting state.
• Assessed sexual orientation using the Kinsey scale.
• Analyzed group differences in fALFF and FC, using identified regions as seeds for FC analysis, and correlated findings with Kinsey scores.

Main Results:

• Homosexual men exhibited increased fALFF in the right middle frontal gyrus and right anterior cerebellum compared to heterosexual men.
• Decreased fALFF was observed in homosexual men in several regions including the left postcentral gyrus, left lingual gyrus, and left inferior frontal gyrus.
• fALFF and FC in specific regions positively correlated with Kinsey scores in homosexual participants.

Conclusions:

• Observed differences in fALFF and FC suggest that male sexual preference is associated with distinct patterns of brain activity.
• These findings point to potential influences of sexual preference on the default mode network's activity patterns.